Electbopneumatic brake



Dec. 20, i927. 1,653,132

T. H. THOMAS ELECTRGPNEUMATIC B'RAKE Filed Feb. 23. 1927 SO 45 lNvz-:NTOR

THOM AS H.T HO MAS AT 'VORNE @en Zd, 1227@ tionen ain Bum vnnnsv'nvanra 1S H. Tlf-IGMS, EDGEV/'QOD, PEIE'NSYLVANIA, A SSGNOR EO TEE FJESTING- E CGMJANY, Gli' W'L/IERDNG, PENNSYLVANIA, A CRORATIGN ELECTROPNEUMATC BRAKE.

application led February 23, 1927. Serial No. 170,071.

This invention relates to 'electro-pneu matic brakes and more particularly to a brake equipment :tor electrically controlling the brakes on a locomotive and cars in a train.

The principal object of my invention is to provide an improved electro-pneumatic brake equipment ot the type in which the brakes are controlled by current iioiv through a single train Wire.

In the accompanying drawing; Fig. 1 is a diagrammatic vieiv ot electro-pneu matic brake equipment embodying my invention; and Fig. 2 is a sectional, diagrammatic vieW o' the pneumatic equipment employed on each car and having associated therewith the electric controlling means.

As shown in Fig. 1 ot the drawing, the electric equipment on the locomotive comprises a brake switch device 1, an alternating current generator 2, an alternating current generator 3, each ot ditterent cycles, such as 25 and 60 cycles respectively7 and transformer having a primary coil et and a secondary coil 5. rl`he electric equipment on each car may comprise a magnet valve device 6 and a magnet valve device 7 each connected in parallel with a single train Wire 8 and having in the branch circuit to each magnet valve device, condensers 9 and 10, respectively.

fr shown in Fig. 2 of the drawing; the magnet valve devices 6 and 7 on each car are associated with a pneumatic valve device 11y including the usual brake cylinder 12 and auxiliary reservoir 13.

The brake switch device 1, shovn in development in Fig. 1, comprises a contact drum,- adapted to be rotated through the several positions shown and in cach position to make the electrical connections shown. The brake sivitch device may be built integral With the usual automatic brake valve device and is adapted to operate simultaneonsly, With the brake valve device.

The' 25 cycle alternating current generator 2 connected in series with the transformer primary coil il and the circuit is controlled by the connections in the brake switch 1. The 60 cycle alternating current generator 3 is adapted to be connected in series with the transitormer secondary coil and the train vvire 8 and its circuit is controlled b v the connections in the brake switch 1.

The inagnetvalve device 6 comprises a magnet and isprovided with a chamber 14E containing` a valve 15, said valve having a tinted stem extending through a suitable bore in a Wall of the casing and engaging 1n a chamber 16 the iiuted stem ot a vwalve 17, contained in chamber 18. Also contained in chamber 18 is spring 19 adapted to engage the collar ot a stem 20 which is adapted'to engage the valve 17. rhe valves 15 and 17 are adapted to be operated by the magnet 6.

rlthe magnet valve device 7 comprises a magnet adapted to operate the double beat valve 21 contained in chamber 22. the lower valve having a tinted stem lextendingthrough a bore in the Wall of the casing and engaging the collar ot a stem 23. Said collar being acted upon by a spring 2a contained in chamber 25. The liuted stein oi the upper valve extends through a chamber 26 which is connected to the atmosphere through the exhaust passage 27.

The condenser 9, in circuit With the mag net 6, is ot such capacity as to-provide a resonant circuit only when subject to a current of 60 cycle frequency such as supplied by the alternating current generator 3 and the magnet valve d vice 6 Will be operatet only when current at 60 cycles trequencv is supplied through the train wire 8, u

The condenser 10, in series with the magnet 7, is adapted to provide a resonant circuit only' when subject to a current of 25 cycles frequency such as supplied by the alternating current generator 2 and the magnet valve device 7 will be operated only at a frequency ot 25 cycles. i

The single train Wire 8 is adapted to be ionnected etyveen and the locomotive by suitable electrical connectors or jumpers 2S, so as to provide one continuous train n'ire throughout the train.

rilhe pneumatic valve device 11 is similar to that disclosed in my prior iatcnt No. 1,440,421, granted January 2, 1923, and may comprise a quick action triple valve device 29, a selector valve portion 30, and a pipe bracket 31 having :faces to which said triple valve device and selector valve portion applied.

The quick action triple valve device comprises ing having a piston chamber conne yted through passage to the usual brke pipe and containing a piston and a valve chan'iber connected through passage 3T to the auxiliary reset'` voir 13 and containing a main slide valve 38 and an auxiliary slide valve 39, adapted to be operated by said piston.

The quick action portion of the triple valve device comprises the usual quick action piston 40, contained in chai'i'iber 41, and a brake pipe vent valve 12, contained in chamber i3 and adapted to be operated by said piston. The usual check valve sl-lV is also contained in chamber nected through `passage @e3 to ch containing the, doulle leat 'valve 2l, and

containing a piston' subject to the pres` sure of coil spring l 1 g a. valver chamber 49, connected tl `issages and 51 to the triple valve pissen chainl 32, and containii a slide valve 52 adaptL to be operated by said pieton.

The magnet valve devices anc. l mounted on a bracket integral i'vith the se lector valve portion 'casing 30 In operation the lluid pressure brake system is charged in thc usual manner and iluicl from the brake pipe 34tlloivs to piston chamber 32'01"` the triple valve device 29 and thence thro'ugli the feed Vgroove to Valve chamber 3 yand lthrough passage 37 to A.ne auxiliary rese voir 13.

Fluid under pressure supplied from the brake pipe and pis of on chan'ib'er the triple valve device 29, through pa 5l and 5 to the selector valve chamber L19 and to the 'spring chambers 18 and In the Iminding' position ot the brake talveand lor-alie swit i l., the alternating ci rent generator 3 i" 'connected to the single train Wire 8 through Contact ot the brake switch 1 and a `ctur'ent 'SO cycles frequency suiiplie'd to the `in Wire. The conden 9 and magnet t3 a resonant circ only with a GO cycle cum-ent. the r is :energized and the vmagnet deenergleed. The circuit is closed through the ground 71 on the ca VThe magnet "4' being ifleanergizcd, the double beat valve 21 is seated in is upper position, thereby l'aermitting 'fluid under pre eure in spi" 1,0' chamber to tion' into valve chamber 2:. "ad thence through passage 4G to the selector 'valve piston chamber 45, wherein the pressure equ'alizes with the opposing' p" re in valve cliei'iber 49, .so that the rnesu'e ol spring .i holds rthe selector valve pislon el? and slide valve in release po ton, as shown in the drawing. et (5 being energia-ed. the ,'alve is seated and the valve 17 is unseated, which permits luid at bralie pipe pressure in chamber 1S to flow past the ral chamber 16 and thenc thro y and pipe 5o to the reservo.A urging said reservoir. Passage also leads to the a une;y o

seat of the selector slide valve but is lapped by the slide valve in release position.

In release position of the selector valve and the triple valve slide valves, the brake cylinder 12 is connected to the atmosphere through passages 58, 59, GO, past the ball checlr valve 6l, passage ,62, cavity (S3 in the main slide valve 33 of the triple valve dcvice 29, passage 64, cavity in the selector valve slide valve 52, and the atmospheric erzl'laust passage G6.

It it is desired to effect a service application of the brakes, the brake valve and brake switch 1 is turned to service position, in which the brake pipe pressure is reduced through the brake valve device in the usual manner. The circuit of the 25 cycle generatorr2 is closed through the contact 67 in the brake switch 1 and the 25 cycle curn rent in the primary coil 4 is induced in the secondary coil 5 ot the transformer. .The circuit of the 60 cycle alternating current generator 3 is breiten in 'service position and the train Wire S, connected to the seconda'ry traiislormer coil 5, is connected through contact G8 and 69 to the ground 70 on the locomotive. The condenser 10 and magnet i forming a resonant circuit only with a current of 25 cycles frequency, the magnet 7 becomes energized and the mag net 6 is deenergized.

Energization of magnet 7' seats the double beat valve 22 in its 4lower position and closes communication ljietween chambers 25 and andl connects chamber 22 to chamber' 26. Fluid under pressure from the selector valve piston chamber Ll5 is then vented to the atmosphere through passage 6, the double beat valve chamber 22, and Achamber ".25 to the atmosplieric exhaust passage 27 which slide Valve downwardly to service position,

against the pressure oilt sp ,Y ice position, the bralie cylrnder p is lapped by the slide valve 52 and pas 55 'is uncovered, 'so that valve chamber is connected to passage 55.

The magnet G'being dceneruized, the va 1T is seated and the valve 15 is uuseated. which permits fluid under pr ure troni the brake pipe to be vented to the lewin cylinder l2, through passages 5l and 50, selector valve chamber 4.9, passage reseV ervoir 57, chamber 1G in the 'mw iet valve device (S, past the valve 15, then-:fe throucjh passage 7l, past ball check valve thro1 passage 73, cavity 74 in the selector Valre slide -valve 52, passages T5, G2, 59 and "'2 to the brake cylinder 12.

'lhe brake pipe pressure is therefore lo cally reduced on each car by operation ot the magnet 6, and is valso reduced by the automatic brake valve device, so that vthe triple valve devices on theitrain are shifted liu lill) to service position, in which the usual service port- 76 in the main slide valve 38 registers With the brake cylinder passage 62 and fluid under pressure Lis supplied 'from the valve chamber 36 and the auxiliary reser- Voir 13 to the brake cylinder 12, in the usual manner.

lt itis desired to limit the degree of brake cylinder pressure and therefore ot the brake application, the brake switch and brake valve are moved to lap position, in which the circuit oi the 25 cycle alternating current generator 2 is closed through the contact 67 ot the brake switch 1 and thereby induces a current ot 25 cycles 'frequency in the train wire 8, which energizes the inagnet 7 and maintains the doublev beat valve 22 and the selector piston and slide valve inservice positon. The circuit or' the 60 cycle alternating current generator 3 is also closed through contact 77 ot' the brake switch 1, so that a current ot' 60 cycles frequency is also supplied to the train Wire 8 and operates to energize the magnet 6, so 'that the magnet operates to unseat the valve 17 and seat the valve 15, and thereby further flow ot' iluid under pressure to the brake cylinder 12 is prevented.

The brake Valve device being in lap position prevents anyY further change in brake pipe pressure, so that when the pressure of the fluid in the auxiliary reservoir 13 becomes reduced by tlow to the brake cylinder, to a degree slightly less than the pressure ot the fluid in the brake pipe, the triple valve piston and auxiliary slide valve are shi't'ted to lap position.

The brake cylinder pressure may be increased in steps as desired by alternately moving the brake valve and switch between service and lap positions, as will be evident.

The. brakes may be released by first rnovl ing' the brake valve and switch to release G ul position and then to running position. ln release position, fluid is supplied from the main reservoir through the brake valve device to the brake pipe in the usual manner, to secure a rapid increasein brake pipe pressure and thereby cause the movement of the triple valves to release position. y

ln release position, the brake switch operates to close the circuit of the 60 cycle alternating current generator 3 through contact TT oi" the brake switch 1 and to close the circuit ot the 25 cycle alternatingl current generator 2 through contact 78 of the brake switch 1, so that both the magnets 6 and 7 vare energized, the same as in lap position,

so that while the selector piston and slide valve are niaintained in their lower position. communication 'lroin the brake pipe to the brake cylinder is cut ott' by the closing ot the valve 15.

Viren the brake pipe pressure has been increased, in release position of the brake valve and switch, sufficiently to eect the movement ot the triple valve to release position, the brake valve may be turned to running position in which the circuit of the 25 cycle alternating current generator 2 is opened, so that the magnet 7 is deenergized and the pressure oit spring 2li shi'tts the double beat valve 22 to its upper position, in which brake pipe iluid from the selector valve chamber 4-9 is supplied through passage 50 to chamber 25, past the valve 21 and thence through passage 4:6 to the selector piston chamber 45, The piston 47 and slide valve 52 are then shifted to release position, in which t-he brake cylinder is connected to the atmospheric exhaust .passage 66.

li the brake valve and switch are lett in running position, the brakes will be fully released, lout if it is desired to effect a graduated release ot the brakes, the brake valve and switch may be moved from running to release position, after the brake cylinder pressure has been partially reduced, so as to cut the further exhaust of fluid in 'the b cylinder. Further reductions in brake cylinder pressure may then be eli'ected by moving the brake valve and switch between running and release position, will be evident.

rlhe electrical connections on the brake switch are the same in holding position as in lap and release position, so that it' desired, the brake valve and switch may be moved between runningl and holding or lap positions, to produce a graduated release of the brakes. T he use ot holding position may be desired under certain conditions to prevent overcharge ot the brake pipe, since in holding position the brake pipe is charged through the usual feed valve device,

An emergency application ot the brakes may be effected by moving the brake valve and switch to emergency position, in which the brake pipe pressure is suddenly reduced at the brake valve and in which both the electric circuits are opened, so that the niagnets G and are deenergized. Y Since the magnet 7 is deenergized, the piston 47 of the selector valve device will be maintained in release position, the supply oi fluid under pressure to the piston chamber 45 being maintained past the open double beat valve 21.

The magnet G being deenergized, the valve 17 is closed and the valve 15 opened, so that fluid under pressure is supplied troni the normally charged reservoir to the quick action piston -lO ot the triple valve device through pipe passage 55, chamber 16, valve chamber 1l. passage 71, check valve '172. passage 73, cavity 7l in the selector slide valve passage 79 and thence to the quick action piston chamber l1 Said piston then operates to open the brake pipe vent valve Ll2 anu vent chamber el?) to loo the brake cylinder. The Huid under pressure in the `brake pipe then lifts the check valve dei and lions into chamber and thence to the brake cylinder, to effect a local reduction in hralre pipe pressure in the usual manner. The triple valve device is thereby quiclrly shifted to emergency position, in which the emergency port 80 registers with the brake cylinder passage 62, so that the [luid under pressure in the auxiliary reservoir 13 permitted to equalize into the brake cylinder.

It a car equipped with the above described apparatus is placed in a train not provided Withfelectric control, the magnets and 7 Will'bcth deenergized, so that the valve 17 Will be seated, cutting oli' the supply of fluid from the brake pipe tothe rese 1voir 57, Whilev the valve 'l5 will be opened', 'and fluid in said reservoir will be vented to the chamL ber above the quick action piston 40'and thence to the' bral're Vcyli der l2.'

o Since-there is no fin l re 'ure in the reservoir 57 under the above conditions, thereivill be no action of theclectric portion andthe equipment of the train will operate only pneuinatically in the usual mannen YAs hereinbeiiore described, the apparatus operates both electrically and pi;cuinatically4H that is to say, the brake pipe pre cure is reducedy in electric operation and the triple valve devices operate by the redi'iction in brake pipe pressure to supply fluid to the brake cylinder.

If'it is desired to operate electrically only7 Without having the triple valve devices iiunction, a plug 81 in passage 82 leading from the valve rchamber 36 to the passage 50 is removed Vand placed in thethreaded opening 83 in the passage'l, so as to close the brake pipe passage "5l and open the auxiliary reservoir passage With this arrangement it will be seen that upon 'operation oi the electric portion, fluid under pressure will be talren tromthe aux-A iliary Areservoir instead ot from the brake pipe in making an Vapplication of the brakes. In this case, theV electric switch 'l loperates independently of the usual auton'iatic brake valve device, so trat no vreduction in brake pipe pressure is 'effected in electric service position'. i

ln maling an electric service application ot the brakes@ thc auxiliary reservoir i n sure lends to be reduced by 'tlou' to the b1 tfvluider` but the pressure in said reservoir non' will be substantially maintained by iroin the brake pipe thi-oi oh tced 52S, on account ol the anton device remaining in running pos which tluid under pressure is supp-K the bral-:e pipe in the usual manner.

In Fig. l or" the drawing7 the rlecc pneumatic hrale apparatus isshoivn anplied only to a car, and not to the locomotive.

Said apparatus may, if desired, be also emptoyedon the loco1notive, and particularly in case of purely electric control, 'it would be desirable to equip the locomotive.

In the foregoing description yI have mentioned the use of tivo alternating current generators of and 60 cycle frequency. I do not desire to restrict my invention to the use olf such frequencies, since any twodif- 'ferent frequencies may equallyY Well be ernployed, it being understood that the magnets and condensers Will then be so designed as to provide the required resonant circuits to correspond with theV lcycle frequencies enr ployctl. i y

Haring now described my invention, what I claim as newand dsir'eto 'secure by Letg ters 'Patent7 is w l. In an electro-pneumatic brake, the conibinatin with a singleitrainvvire and electrically controlled `meansV operated-by curi npiilied from said'trainwire for coning the brakes1 oftwo alternating cui rent generators. adapted to *supply* current at dit rent- Jircquencies to said'train Wire.

In an electro-pneumaticbrake, Lthe combination with a single train `Wire and ele-c i-ically ccntrolied means operated'by currcnt supplied i'i'oin'said"l train Wire for controlling the b1'akes',of'tivo alternating c'urrent generatorsyone adapted yto supply current at one frequency' to'said tra-in'wire and the other adaptedto"supplyzcurrent at a diillerent frequency to saidA Wire.'-

3. In an electro-pneumatic brake, the com` bination With a single train Wire of velectrically controlled devices for controlling the brakes, one responsive only to vcurrent supplied at one frequency through said vv'ire andthe other responsive only-Ito current at another yfrequency, and generators for-snp# plying current at the different `frequencies to said train Wire.

l. vIn anelectro-pneumatic brake, the com-- bination with a single train Wire, of electrically controlled devices= arranged on parallel circuit with said train Wire for controlling the brakes,a condenser in circuit with cach device Vadapted to permit flow of alternating current through each'dcvice only at diil'erent frequenci es;`r and electric generators ifor supplying alternating current lat the dillerent Jfrequencies to said train Wire.

In an elcctio-pneuniatic brake, the coinu bination with a single train wire and electrically controlled. devices operable by alternating current supplied at ditferc-nt 'Frequencies to said train wire, ot a transformer.having a primary and a secondary coil^ an electric' generator adapted to be connected through the secondary coil to said train Wire, and a second generator adapted to supply current to said primary coil.

G. In an electro-pneumatic brake, the combination with a single train Wire and electrilil() lll) cally controlled devices operable by alten nailing current supplied at clierent frequencies to said train Wire, of a transformer having a primary and a secondary coil7 an alternating current generator adapted to supply current at one frequency through the secondary coil t0 said train Wire, and a second alternating current generator adapted supply current at a different Yfrequency to said primary coil.

vIn testimony whereof I have hereunto set my hand.

THOMAS H. THOMAS. 

